Rotary regenerators typically comprise a core in the form of a disc having many passages through which exhaust gas and cool air alternately pass. While the exhaust gas is passing through the regenerator core the walls of the passages therein heat up. The heat is then transferred to the cool air as it passes through the same passages.
Seals in contact with the faces of the regenerator guide the hot has and cool air through designated portions of the core while the core rotates beneath the seals. Thus, each individual passage passes cyclicly from the ot gas environment to the cooler air environment and back. In this manner, heat is continuously transferred from the hot gas to the relatively cooler air being inducted into the engine. In a turbine, the cool air comprises compressor discharge air at high pressure, and the hot gas exhaust gas. Because the cool air is at high pressure, substantial leakage can occur at the seals, reducing the regenerator's usefulness. While much effort has been spent to minimize leakage through regenerator seals, there is a need for further improvement in seal performance